Iphone connecting to the internet

Hello, i've got a problem and I'm confused.

The problem is that my iphone is very often connected to the internet while wifi is disconnected and edge not configured.

I mean, sometimes I recieve e-mails and am able to connect to the internet while wifi is off. I have never configured Edge and in the settings it is set as off.

Firmware version is 1.1.4. Any advice?

Because when the APN settings are blank the phone is able to get them from the operator.
That's why I always put dull information to prevent it from connecting.